Section 3 - Chemical Recovery

3.6 ELECTRODIALYSIS

3.6.3 Applications and Restrictions

The application of electrodialysis for recovery of nickel plating
chemicals is shown in Exhibit 3-49.
This application, which includes a material balance, was taken
from the literature (ref. 32), and is based on an actual case
study performed by an electrodialysis equipment manufacturer.
The work for this application was performed at a job shop with
an automatic nickel barrel plating operation. The plating and
rinsing configuration used prior to the implementation of electrodialysis
is also shown. Based on a comparison of the two diagrams, the
electrodialysis system recovered approximately 38 lbs of nickel
per day more than the existing drag-out/drag-in recovery rinsing
system. The difference in plating tank evaporation rates between
the original and revised systems was not discussed in the article,
but presumably was due to a change in the operating temperature
of the bath.